Method for producing ammonium octamolybdate composition

ABSTRACT

An isomer of ammonium octamolybdate (“AOM”) and method for producing the same. A new AOM isomer (“X-AOM”) is described which is characterized by a distinctive Raman spectral profile compared with other AOM isomers including α and β-AOM. To produce the novel isomer, ammonium dimolybdate (“ADM”) is combined with molybdenum trioxide (MoO 3 ) and water to yield a mixture. When mixing these materials, optimum results are achieved if at least one of the foregoing molybdenum-containing reagents is added in a gradual, non-instantaneous manner so that the selected reagent is not added to the mixture in a single large mass. This gradual delivery procedure, along with a carefully controlled prolonged heating stage (e.g. in excess of 3 hours) contributes to a maximum yield of high purity X-AOM.

CROSS REFERENCE TO RELATED APPLICATION

This is a continuation of U.S. application, Ser. No. 09/094,194, filedon Jun. 9, 1998, now U.S. Pat. No. 5,985,236, issued Nov. 16, 1999,which is hereby incorporated herein by reference for all that itdiscloses.

BACKGROUND OF THE INVENTION

The present invention generally relates to the production of an ammoniumoctamolybdate composition, and more particularly to the manufacture of anovel and unique ammonium octamolybdate isomer having a number ofbeneficial characteristics.

Ammonium octamolybdate (hereinafter designated as “(NH₄)₄Mo₈O₂₆” or“AOM”) is a commercially-useful molybdenum composition which isavailable in multiple forms or “isomers”. Each isomer is characterizedby its ability to differentially rotate and otherwise reflect lightpassing therethrough. In particular, two main isomers of AOM have beenisolated and used commercially, namely, (1) the α form (“α-AOM”); and(2) the β form (“β-AOM”). Other isomers also exist including the γ form(“γ-AOM”) and the δ form (“δ-AOM”). However, little information isavailable regarding the γ and δ materials which are mostly generated invery small quantities as by-products and are predominantlytheoretical/experimental in nature. Of particular interest from acommercial standpoint is the manufacture of α-AOM which is used as asmoke suppressant in many different compositions including polymericplastic coating materials for electrical wiring and fiber-opticelements. Representative plastic materials suitable for combination withα-AOM include rigid polyvinyl chloride (“PVC”). The β-AOM isomer islikewise secondarily useful for this purpose although β-AOM ispreferred.

In general, α-AOM is traditionally produced by the thermal decompositionof ammonium dimolybdate which shall be designated hereinafter as“(NH₄)₂Mo₂O₇” or “ADM”. This process occurs in accordance with thefollowing basic chemical reaction:

4(NH₄)₂Mo₂O₇+heat→α−(NH₄)₄Mo₈O₂₆+4NH₃+2H₂O  (1)

However, as noted in U.S. Pat. No. 4,762,700 (which is incorporatedherein by reference), the foregoing process is characterized by numerousdisadvantages including the generation of α-AOM having too large aparticle size. As a result, the α-AOM product generated from reaction(1) listed above had to be physically size-reduced using conventionalmaterial-handling procedures which resulted in additional productioncosts and increased manufacturing time.

Another disadvantage associated with the conventional thermal generationof α-AOM involved the production of undesired by-products if thechemical reactants were improperly heated (e.g. over-heated orinsufficiently heated according to U.S. Pat. No. 4,762,700). When thissituation occurred, the following undesired by-products were generated:(1) ammonium trimolybdate (which is also characterized as “(NH₄)₂Mo₃O₁₀”or “ATM”); and (2) molybdenum trioxide (also designated herein as“molybdic oxide” or “MoO₃”). Since neither of these materials have theimportant and beneficial smoke-suppressive characteristics of α-AOM asdiscussed herein, they are undesired in the α-AOM production process.For this reason, the thermal decomposition method outlined above must bevery carefully monitored, which again results in greater labor costs,more extensive processing equipment, and increased margins of error.

To overcome these disadvantages, an “aqueous” or “wet” reaction processwas developed which is extensively discussed in U.S. Pat. No. 4,762,700(again incorporated herein by reference). This process basicallyinvolves the initial combination of ammonium dimolybdate (“ADM” aspreviously noted) with water to yield a slurry-type mixture. In apreferred embodiment, about 50-350 grams of ADM are used per liter ofwater to form the desired mixture. Thereafter, particulate molybdenumtrioxide is combined with the ADM-containing slurry, with the molybdenumtrioxide having a preferred particle size of about 10-300 microns and ahigh purity level (e.g. not more than about 0.5% by weight (total) ofiron (Fe), potassium (K), copper (Cu), lead (Pb), calcium (Ca), andother impurities.) It is further stated in U.S. Pat. No. 4,762,700 thatboth of these materials are specifically combined in the stoichiometricproportions set forth in the following basic formula:

2(NH₄)₂Mo₂O₇+4MoO₃→α−(NH₄)₄Mo₈O₂₆  (2)

The initial ADM-containing slurry product used in the reaction listedabove may be manufactured in many different ways including but notlimited to a combination of water, ammonium hydroxide (“NH₄OH”), andmolybdenum trioxide. The ADM-containing slurry product can be alsoderived from “ADM crystallizer mother liquor”. Finally,commercially-available, pre-manufactured ADM can be directly combinedwith water to yield the slurry. Regardless of which process is employedfor this purpose, U.S. Pat. No. 4,762,700 states that the molar ratio ofammonia to molybdenum (e.g. [NH₃]/[Mo]) in the ADM-containing slurryshould be adjusted to a value of 1.00 prior to addition of theparticulate molybdenum trioxide so that the resulting α-AOM product issubstantially free from undesired impurities including β-AOM, ammoniumheptamolybdate, and other non α-AOM compounds.

Regarding β-AOM, this material is again generated as a side product intraditional thermal decomposition methods. While β-AOM also has smokesuppressant properties, α-AOM is generally recognized as being superiorfor these purposes. Accordingly, β-AOM has only secondary commercialvalue compared with α-AOM as previously noted.

Further information, data, and other important parameters regardingα-AOM and β-AOM will be presented below from a comparative standpoint inorder to illustrate the novelty of the present invention which involvesa new AOM isomer. This unique isomer (designated herein as “X-AOM”)differs considerably from all other forms/isomers of AOM including butnot limited to α-AOM and β-AOM (as well as the γ and δ forms of AOM). Asdiscussed in greater detail below, X-AOM is different from the otherlisted isomers both structurally and functionally.

In accordance with the information provided herein, α-AOM istraditionally used as a smoke control agent in plastic materials andother related compositions. However, the X-AOM isomer offers a number ofbenefits compared with traditional α-AOM including more efficient smokesuppression per unit volume and greater stability/uniformity.Furthermore, as confirmed by sophisticated chemical identificationtechniques (including a process known as “Raman spectral analysis” whichwill be summarized in further detail below), the claimed X-AOM productis likewise characterized by a novel isomeric structure which differsconsiderably from the structure of α-AOM and β-AOM. The use of Ramanspectral analysis enables the X-AOM product to be clearly identified anddistinguished from other isomers of AOM. In addition, X-AOM is producedusing a unique manufacturing process which facilitates the generation ofthis material in a highly-effective and preferential manner onproduction-scale levels.

For these and other reasons discussed in the Detailed Description ofPreferred Embodiments section, the present invention represents aconsiderable advance in the art of ammonium octamolybdate production.The claimed invention specifically involves (1) the generation of astructurally novel isomeric AOM product which provides many importantfunctional capabilities; and (2) the creation of a specializedmanufacturing method which enables the X-AOM product to be produced inhigh yields with a considerable degree of purity. Accordingly, thepresent invention is novel, unique, and highly beneficial in many waysas outlined in greater detail below.

SUMMARY OF THE INVENTION

The following summary is provided as a brief overview of the claimedproduct and process. It shall not limit the invention in any respect,with a detailed and fully-enabling disclosure being set forth in theDetailed Description of Preferred Embodiments section. Likewise, theinvention shall not be restricted to any numerical parameters,processing equipment, chemical reagents, operational conditions, andother variables unless otherwise stated herein.

It is an object of the present invention to provide a novel isomer ofammonium octamolybdate (“AOM”) and method for producing the same.

It is another object of the invention to provide a novel AOM isomer andmethod for producing the same in which the isomer is characterized by aunique Raman spectrum (and arrangement of intensity peaks associatedtherewith) which is entirely distinguishable from other AOM isomersincluding but not limited to the α and β forms of this material.

It is another object of the invention to provide a novel AOM isomer andmethod for producing the same in which the claimed method is able togenerate large quantities of the desired isomer (designated herein as“X-AOM”) with a maximum degree of purity and efficiency.

It is another object of the invention to provide a novel AOM isomer andmethod for producing the same in which the method of interest employsreadily-available materials and a minimal number of processing steps.

It is another object of the invention to provide a novel AOM isomer andmethod for producing the same in which the claimed method facilitatesproduction of the desired isomer in a rapid, operationally-efficientmanner with minimal labor requirements.

It is a further object of the invention to provide a novel AOM isomerand method for producing the same in which the claimed method avoids themanufacture of other AOM isomers, thereby resulting in a highly pureX-AOM product.

It is a still further object of the invention to provide a novel AOMisomer and method for producing the same in which the claimed method isfurther characterized by the use of minimal reagent quantities in orderto provide a cost-efficient, highly-effective X-AOM production system.

It is an even further object of the invention to provide a novel AOMisomer and method for producing the same in which the claimed productand method result in a unique composition (X-AOM) which providesimproved smoke suppression capacity per unit volume and greateruniformity/purity levels compared with other AOM products (includingα-AOM).

The claimed invention involves a unique, novel, and previously-unknownisomer of ammonium octamolybdate [(NH₄)₄Mo₈O₂₆] which, for the purposesof identification, shall be characterized herein as “X-AOM”. Isomerstraditionally involve compounds which are different yet have the samemolecular formula as discussed in Morrison, R. T., et al., OrganicChemistry, Allyn and Bacon, Inc., Boston, 3^(rd) ed., p. 37 (1973). Froma structural standpoint, individual isomers have a different arrangementand orientation of atoms relative to each other. These dissimilaritiestypically lead to substantial differences in chemical properties fromone isomer to another. Ammonium octamolybdate isomers (particularly theα isomer which is conventionally designated herein as “-AOM”) have beenemployed as smoke suppressants in various materials including electricaland fiber-optic cables produced from polymeric plastics. Uponcombustion, plastic materials which employ α-AOM therein will generateless smoke compared with compositions which lack any α-AOM. The novelisomer claimed herein (“X-AOM”) provides superior smoke suppressivebehavior per unit volume compared with conventional AOM isomers(including α-AOM). The X-AOM isomer therefore offers a considerabledegree of utility in many important applications.

The following discussion again constitutes a brief overview of thepresent invention and its various features (including the uniquedistinguishing characteristics of X-AOM compared with other AOMisomers). Unless otherwise stated herein, the claimed process shall notbe restricted to any numerical production parameters, processingequipment, and reagents used to generate the X-AOM product. Theinvention in its broadest sense shall therefore be defined in accordancewith the claims presented below.

To produce X-AOM in a preferred embodiment, a number of process stepsand reagents are employed. However, before a summary of these items isprovided, an overview of the distinguishing characteristics of X-AOMrelative to the other isomers of ammonium octamolybdate (“AOM”) is inorder. The X-AOM product is readily characterized (and clearlydistinguished from all other forms of AOM) using its unique Ramanspectral profile which includes a number of distinctive peaks that arenot present in the Raman spectral profiles of other AOM isomers. Asoutlined in further detail below, Raman spectral analysis basicallyinvolves a collection of spectral intensity values which are producedwhen light obtained from a high-energy source (e.g. a quartz-mercurylamp or argon-ion laser unit) is passed through a substance. Ramanspectroscopy is an established analytical technique that provides highlyaccurate and definitive results. In accordance with the presentinvention, Raman spectral analysis of the novel X-AOM product yields aunique spectral profile having three (3) main intensity peaks which aredistinctive and not present in the spectral profiles of other AOMisomers. These main peaks involve the following values: Peak #1=about953-955 cm⁻¹; Peak #2=about 946-948 cm⁻¹; and Peak #3=about 796-798cm⁻¹. The foregoing values are completely distinguishable and absentfrom the Raman spectral profiles associated with the other main AOMisomers listed above including (1) α-AOM [two main peaks]: Peak #1=about964-965 cm⁻¹; and Peak #2=about 910-911 cm⁻¹; and (2) β-AOM [two mainpeaks]: Peak #1=about 977-978 cm⁻¹; and Peak #2=about 900-901 cm⁻¹.Regarding the term “main peaks”, as used above, this term shallencompass peaks for any given AOM isomer which are not present in theRaman spectral profiles of other AOM isomers. In accordance with thisinformation (which clearly distinguishes X-AOM from the other AOMisomers listed above), the creation of X-AOM represents a new, unique,and significant development in the art of molybdenum technology.

The use of Raman spectral analysis involves the most feasible andpractical way of identifying X-AOM, with this method being accurate,repeatable, and subject to minimal error. It is therefore entirelysufficient, enabling, and definitive for the claimed X-AOM isomer to becharacterized (e.g. identified) spectrally, particularly using Ramanspectral profile techniques. Additional information, along with adetailed overview of the Raman spectral data associated with X-AOM (andother AOM isomers) will be provided below in the Brief Description ofthe Drawings and Detailed Description of Preferred Embodiments sections.

To manufacture X-AOM with acceptable purity values (e.g. +95% by weightpure) while avoiding the production of other AOM isomers (particularlyα-AOM), a unique and specialized procedure for accomplishing this goalwill now be summarized. While the specific molecular basis for thepreferential production of X-AOM using the claimed process is notentirely understood at this time, a number of process steps areconsidered to be of primary importance as identified herein.

The first step in producing X-AOM involves initially providing (A) asupply of ammonium dimolybdate (e.g. “(NH₄)₂Mo₂O₇” or “ADM”); (B) asupply of molybdenum trioxide (e.g “molybdic oxide” or “MoO₃”); and (C)a supply of water (which, in all of the embodiments set forth herein,should be deionized). The molybdenum compositions listed above arecommercially available from numerous sources including but not limitedto the Climax Molybdenum Company of Ft. Madison, Iowa (U.S.A.). However,as indicated in U.S. Pat. No. 4,762,700 (incorporated herein byreference), ADM may be conventionally manufactured in accordance withthe following formula:

2NH₄OH+2MoO₃→(NH₄)₂Mo₂O₇+H₂O   (3)

In the formula listed above (and in the other formulae presentedherein), “NH₄OH”=ammonium hydroxide. Molybdenum trioxide may also beproduced using many alternative processing techniques including theroasting of molybdenum sulfide (“MoS₂”) to form molybdenum trioxide asindicated in U.S. Pat. No. 4,046,852 or the use of a multi-slurryoxidation process as described in co-owned U.S. Pat. No. 5,820,844, bothof which are incorporated herein by reference. However, this inventionshall not be restricted to any particular methods for producing ADM,molybdenum trioxide (or any other reagents set forth herein), with thespecific procedures listed in this summary and the Detailed Descriptionof Preferred Embodiments section being provided for example purposesonly. Likewise, the term “providing” as used in connection with anygiven reagent shall encompass (1) adding the reagent in pre-manufacturedform obtained from, for example, a commercial supplier; or (2)generating the desired reagent in situ during the production process bycombining the necessary ingredients to generate the reagent on-demand,with both methods being considered equivalent.

The compositions listed above are then combined with a supply of waterto produce an aqueous chemical mixture. However, three different methodsmay be employed to generate the aqueous chemical mixture. The first andsecond methods are related and basically involve initially selecting oneof the ammonium dimolybdate (“ADM”) and molybdenum trioxide supplies foruse as a “first reagent”, and thereafter selecting another of the ADMand molybdenum trioxide supplies for use as a “second reagent”.Normally, when the material to be used as the first reagent (either ADMor molybdenum trioxide) is initially chosen, selection of the secondreagent will involve the material which is “left over” and not used asthe first reagent. In a first embodiment of the invention, the firstreagent will involve ADM, with the second reagent consisting ofmolybdenum trioxide. In the second embodiment, molybdenum trioxide willbe used as the first reagent, with the second reagent consisting of ADM.The only difference between the first and second embodiments involvesthe particular materials that are used as the first and second reagents,with the first reagent being added into the system before the secondreagent as discussed below.

Once a selection is made as to which compositions will be employed asthe first and second reagents, both embodiments are substantially thesame. Specifically, the first reagent (either ADM in embodiment number(1) or molybdenum trioxide in embodiment number (2) is initiallycombined with the supply of water to yield an aqueous intermediateproduct. The second reagent (either molybdenum trioxide in embodimentnumber (1) or ADM in embodiment number (2)) is then added to theintermediate product in a controlled, gradual, and non-instantaneousmanner over time to yield the aqueous chemical mixture.

A third embodiment of the claimed process involves a situation in whichthe ADM and molybdenum trioxide are combined with the supply of watersimultaneously (e.g. both at the same time). The delivery of bothmaterials shall be undertaken in a controlled, gradual, andnon-instantaneous manner over time to yield the aqueous chemicalmixture. In this particular embodiment, an intermediate product is notgenerated since all of the reactants are added into the systemsimultaneously.

It should also be noted that any terminology in the present descriptionwhich indicates that ADM or molybdenum trioxide is “added”, “combined”,or otherwise delivered into the system shall again involve the use ofthese materials in a pre-manufactured form, or the addition of“precursor” compounds which, when combined, react in situ to form thedesired reagent(s)/ingredients. Likewise, when the term “combining” isused herein to generally involve mixing of all the listed ingredients toproduce the aqueous chemical mixture, this term shall encompass theaddition of such materials in any order (and in any manner eithergradually or non-gradually) if the order or delivery mode is notspecifically designated in the claim or example under consideration.

In accordance with currently available information, a novel feature ofthe claimed process which, in a preferred embodiment, is currentlybelieved to at least partially contribute (in most cases) to thepreferential production of X-AOM over other AOM isomers is the use of atechnique which involves “gradual, non-instantaneous” addition of theselected reagent(s) as previously noted. This phrase shall signify atechnique in which the composition of interest is not added to the water(or aqueous intermediate product depending on which embodiment isinvolved) all at once, but is instead delivered in a gradual andprogressive manner at a pre-determined rate (e.g. a specific quantityover a designated time period). Controlled and gradual addition mayinvolve (A) continuous delivery of the desired material(s) at a constantand uniform rate over the selected time period; or (B) delivery of thedesired material(s) in discrete amounts (e.g. allotments) at periodicintervals over the chosen time period. This particular technique(regardless of which variant is employed) is designed to avoiddelivering all of the selected materials(s) into the system at one timein a single large mass. Accordingly, when a particular composition (e.g.ADM, molybdenum trioxide, or both) is selected for delivery in a“gradual, non-instantaneous manner”, this phrase shall again encompassany procedure in which the composition is not added into the system allat once, but is instead accomplished over time. While not entirelyunderstood, it is believed that this delivery method creates a complexkinetic environment which promotes the formation of X-AOM in most cases.

The claimed process shall not be restricted to any particular additionrates in connection with chemical compositions that are delivered in a“gradual, non-instantaneous manner”. However, to provide optimumresults, the “gradual, non-instantaneous” addition of ADM and molybdenumtrioxide typically involves a delivery rate of (1) about 75-150kilograms per minute for ADM; and (2) about 65-130 kilograms per minutefor molybdenum trioxide. These rates (which may be varied as needed inaccordance with preliminary pilot studies) are applicable to all of theembodiments set forth herein as outlined below.

The invention shall also not be limited to any particular numericalquantities in connection with the supplies of ADM and molybdenumtrioxide. It is nonetheless preferred that such materials be employed inthe approximate stoichiometric proportions provided by the followingchemical reaction:

2(NH₄)₂Mo₂O₇+4MoO₃→X−(NH₄)₄Mo₈O₂₆(or “X-AOM”)   (4)

However, to achieve optimum results, it has been determined that the useof molybdenum trioxide in a slight excess of stoichiometric requirements(e.g. about 1-5% by weight excess molybdenum trioxide) is preferred.

After formation of the aqueous chemical mixture using any of thetechniques listed above, the mixture is thereafter heated to generate acompleted reaction product having the X-AOM isomer therein (in solidform). While the claimed method shall not be restricted to anyparticular heating parameters in connection with the aqueous chemicalmixture, it is preferred that the mixture be heated to a temperature ofabout 85-90° C. over a time period which should exceed 3 hours (e.g.about 3.5-5 hours). Likewise, optimum results are achieved if theaqueous chemical mixture is constantly agitated (e.g. stirred) duringthe heating process to ensure a maximum yield of X-AOM with high purityvalues. It is also believed that heating of the aqueous chemical mixturein accordance with the numerical parameters listed above (especiallyover a time period which exceeds 3 hours) contributes to thepreferential generation of X-AOM over other AOM isomers including α-AOMwhen used with or without the gradual, non-instantaneous additionprocedures listed above. However, a combination of both techniques (e.g.gradual, non-instantaneous addition and the time/temperature parameterslisted above) provides best results.

After heating as previously noted, the reaction product is optionally(but preferably) cooled to a temperature of about 60-70° C. which isdesigned to provide additional ease of handling and the furtherpromotion of X-AOM crystal growth. The cooled reaction product isthereafter processed to physically remove the solid X-AOM therefrom.This may be accomplished in many different ways, without restriction toany particular isolation methods. For example, in a preferred andnon-limiting embodiment, the X-AOM-containing reaction product can bepassed through a selected filtration system one or more times as neededand desired (with or without the use of one or more water-washingsteps). The resulting X-AOM product is thereafter dried and collected tocomplete the reaction process. The final X-AOM composition ischaracterized by a high degree of purity (+95% by weight X-AOM) and adistinctive Raman spectral profile as outlined below in the DetailedDescription of Preferred Embodiments section.

In a still further alternative embodiment of the invention which isdesigned to produce an X-AOM product with a fine, easily-handledconsistency, a supply of previously manufactured X-AOM (e.g. X-AOMgenerated from the previous production run) is retained and combinedwith the water, ADM, and molybdenum trioxide at the initial stages ofthe process. Preferably, a portion of the aqueous chemical mixturediscussed above (which contains X-AOM therein) is used for this purposewhich provides the foregoing benefits along with a “seed” function thatprovides improved X-AOM yield and handleability characteristics byincreasing the overall density of the X-AOM. The resulting mixture isthen heated as discussed above (e.g. using the above-listed parameters)to yield a reaction product containing additional amounts of X-AOMtherein. This particular development is applicable to all of theembodiments set forth herein regardless of whether gradual ornon-gradual component addition is employed, and is not limited to anyother reaction conditions.

While the claimed method shall not be restricted to any numerical orother parameters (including those listed above unless otherwise statedherein), an exemplary procedure which yields optimum results involvesthe following steps: (1) providing a supply of ammonium dimolybdate(“ADM”), a supply of molybdenum trioxide, and a supply of water; (2)combining the ADM with the water to produce an intermediate product,with about 283 grams of ADM being used per liter of water; (3) combiningthe molybdenum trioxide with the intermediate product generated inaccordance with step (2) to yield an aqueous chemical mixture, withabout 0.87 grams of molybdenum trioxide being used per gram of ADM,wherein this step involves adding the molybdenum trioxide to the aqueousintermediate product in a gradual, non-instantaneous manner (definedabove) at a rate of about 110 kilograms of molybdenum trioxide perminute in order to avoid delivering the molybdenum trioxide to theintermediate product all at once; (4) heating the aqueous chemicalmixture at a temperature of about 88° C. for a time period of about 4.5hours to generate a completed reaction product containing the desiredammonium octamolybdate isomer therein (e.g. X-AOM); (5) cooling theX-AOM-containing reaction product to a temperature of about 66° C. afterit has been heated in accordance with step (4); and (6) removing thesolid X-AOM composition from the liquid fractions of the reactionproduct after it has been cooled pursuant to step (5) (e.g. usingfiltration or other equivalent techniques). Implementation of thisprocedure results in the highly effective manufacture of X-AOM at puritylevels of +95% by weight X-AOM. This purity level reflects thesubstantial absence of non-X-AOM isomers therein.

In conclusion, the claimed product and process collectively represent animportant development in molybdenum technology. The X-AOM compositiondescribed above is not only characterized by a unique isomeric structure(which is different from other AOM isomers as demonstrated by Ramanspectroscopy), but likewise has improved smoke suppression qualities.The distinctive X-AOM composition is likewise produced in a manner whichenables large quantities of X-AOM to be generated with high purity anduniformity levels. These and other objects, features, and advantages ofthe invention shall be presented below in the following DetailedDescription of Preferred Embodiments.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic representation of the basic process steps whichare employed in a preferred embodiment of the present invention to yielda new and unique isomer of ammonium octamolybdate (e.g. “X-AOM”).

FIG. 2 is a Raman spectral profile of the novel X-AOM isomer claimedherein.

FIG. 3 is a Raman spectral profile of conventional α-AOM which issignificantly different from the Raman spectral profile of X-AOMpresented in FIG. 2.

FIG. 4 is a Raman spectral profile of conventional β-AOM which issignificantly different from the Raman spectral profile of X-AOMpresented in FIG. 2.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

In accordance with the claimed invention, a novel isomer of ammoniumoctamolybdate (“AOM”) is disclosed which is different in structure andfunction compared with all other ammonium octamolybdate isomers(including the α, β, γ, and δ forms of this material). The “isomers” ofa compound traditionally involve compositions which are different instructural configuration yet have the same molecular formula asdiscussed in Morrison, R. T., et al., Organic Chemistry, Allyn andBacon, Inc., Boston, 3^(rd) ed., p. 37 (1973). Specifically, individualisomers have a different arrangement and orientation of atoms relativeto each other. These dissimilarities can lead to substantial differencesin chemical properties from one isomer to another. In the presentinvention, ammonium octamolybdate has the following basic molecularformula: “(NH₄)₄Mo₈O₂₆” which is also known as simply “AOM”. The novelisomer associated with the present invention (characterized herein as“X-AOM”) involves a different structural configuration compared with allpreviously-known isomers of AOM including the α and β forms of thismaterial as discussed below and clearly shown in the Raman spectralprofiles of FIGS. 2-4. The structural dissimilarities between X-AOM andthe other isomers of AOM (α-AOM and β-AOM) are reflected in a number ofbeneficial attributes associated with X-AOM including improved smokesuppression capacity/performance when the X-AOM composition is employedwithin, for example, polymer plastic-based electrical and/or fiber opticcable materials (e.g. made of rigid PVC) as previously noted. Inparticular, it has been determined in certain applications thateffective smoke suppression will occur using reduced amounts of X-AOM asan additive within, for example, polymer plastics compared withconventional α-AOM. Likewise, X-AOM is characterized by significantlevels of stability and uniformity. Regarding the structuraldissimilarities between X-AOM and other AOM isomers, these differencescan again be shown in a definitive manner by Raman spectrographictechniques in accordance with specific information provided below.

As a preliminary point of information, the claimed process shall againnot be restricted to any particular operational parameters includingreagent quantities, the order of reagent addition, reaction conditions,and other numerical values unless otherwise indicated. Specific reactionparameters and other operational factors may be optimized in a givensituation (taking into account environmental factors, production-scalerequirements, and the like) using routine preliminary pilot testing. Thediscussion provided below involves one or more preferred embodimentswhich are designed to provide optimum results and shall not beconsidered limiting or restrictive.

A. The X-AOM Production Method

With reference to FIG. 1, an exemplary and schematic overview of aprocess designed to produce the novel X-AOM isomer of the presentinvention is provided. This process may again be varied as needed basedon routine preliminary testing unless otherwise noted. As shown in FIG.1, the entire processing system is generally represented at referencenumber 10. Within system 10, a supply of ammonium dimolybdate 12 (alsoknown as “(NH₄)₂Mo₂O₇” or “ADM”) is initially provided. This compositionis commercially available from numerous sources including but notlimited to the Climax Molybdenum Company of Ft. Madison, Iowa (U.S.A.).However, as discussed in U.S. Pat. No. 4,762,700 (incorporated herein byreference), ADM may be conventionally manufactured in accordance withthe following formula:

2NH₄OH+2MoO₃→(NH₄)₂Mo₂O₇+H₂O   (5)

In the formula listed above (and in other formulae presented herein),NH₄OH=ammonium hydroxide and MoO₃=molybdenum trioxide. However, thepresent invention shall not be restricted to any particular methods forproducing ADM (or the other reagents set forth herein). As discussed inU.S. Pat. No. 4,762,700, an aqueous solution of ADM which is suitablefor use in the claimed process at this stage could likewise be derivedfrom other sources including “ADM crystallizer mother liquor” obtainedfrom commercial ADM manufacturing processes.

In the present embodiment, the supply of ADM 12 shall be designatedherein and selected for use as a “first reagent” (e.g. the reagent thatis initially added into the system 10). The materials which can beemployed in connection with the first reagent may be different in theother embodiments of the claimed process as discussed further below.While all embodiments of the invention shall not be restricted to theuse of ADM materials having a particular particle size, it is preferredthat a particle size value of about 22-26 microns be employed inconnection with the supply of ADM 12 to facilitate proper mixing anddissolution of this material.

With continued reference to FIG. 1, the supply of ADM 12 (againcharacterized as the first reagent in this embodiment) is then combinedwith (e.g. added to) a supply of water 14 (optimally deionized) which isretained within a containment vessel 16 produced from a number ofpossible materials including but not limited to stainless steel, inertplastic [e.g. polyethylene], and the like. It should be noted at thispoint that any production-scale may be employed in connection with theclaimed process. However, in a representative and exemplary embodimentdesigned for mass-production purposes, the containment vessel 16 willhave an optimum capacity of about 20,000-25,000 liters although smalleror larger vessels may be used as desired. All of the remaining processsteps associated with the claimed method which are used to produce thedesired aqueous X-AOM-containing chemical mixture (discussed below) ineach of the embodiments set forth herein can be implemented within thecontainment vessel 16. However, to ensure rapid processing on a largescale, the multi-vessel configuration specifically shown in FIG. 1 ispreferred.

While not required, the supply of water 14 inside the containment vessel16 may be pre-heated to facilitate immediate dissolution of the ADM 12(and other materials) in the water 14 during subsequent stages of thereaction process. To accomplish pre-heating, the vessel 16 will includea heating unit 20 associated therewith which may involve many knownsystems including steam-based, water-flow, electrical-resistance, orhot-water immersion units which are suitable for this purpose. While theprocess discussed herein shall not be limited to a single pre-heatingtemperature, optimum results are achieved if the water 14 is pre-heatedto about 85-90° C. and maintained at this temperature up to and duringthe remaining stages of the reaction process as indicated below.

Addition of ADM 12 to the water 14 within the vessel 16 (whetherpre-heated or not) is thereafter initiated. The manner in which thesupply of ADM 12 is added to the water 14 (e.g. either all at once or ina gradual, non-instantaneous fashion [defined further below]) is notcritical at this stage, provided that the ADM 12 (e.g. the firstreagent) is ultimately dissolved in a substantially complete mannerwithin the water 14. To accomplish this goal, it is preferable to addthe supply of ADM 12 to the water 14 in a gradual, non-instantaneousmanner to ensure rapid and complete dissolution. A representative,non-limiting addition rate will involve about 75-150 kilograms of ADM 12per minute. However, as outlined in greater detail below, it is evenmore important for the second reagent (e.g. molybdenum trioxide in thepresent embodiment) to be added to the water 14 in a gradual,non-instantaneous manner. It is currently believed that this technique,while not completely understood, beneficially contributes in most casesto the preferential generation of X-AOM over other forms of ammoniumoctamolybdate (including α-AOM).

The phrase “gradual, non-instantaneous addition” as employed herein(relative to all of the listed embodiments) shall signify a technique inwhich the composition of interest is not added to the water 14 (or anyintermediate products depending on which embodiment is involved) all atonce, but is instead delivered in a gradual and progressive manner at apre-determined rate (e.g. a specific quantity over a selected timeperiod). This type of controlled, gradual addition may involve (A)continuous delivery of the desired material(s) at a constant and uniformrate over the designated time period; or (B) delivery of the desiredmaterial(s) in discrete amounts (e.g. allotments) at periodic intervalsover the chosen time period. The gradual addition of reagents as definedabove is designed to avoid delivering all of the selected materials(s)into the system 10 at one time in a single large mass. Accordingly, whena particular material is indicated to be delivered in a “gradual,non-instantaneous manner”, this phrase shall encompass any procedure inwhich the selected reagent is not added into the system 10 all at once,but is instead accomplished over time. While not entirely understood, itis again believed that this gradual addition technique creates a complexand unique kinetic environment which promotes the preferential formationof X-AOM.

It is preferred in all embodiments of the claimed process that thecontainment vessel 16 be designed to include a stirring system 22therein (e.g. in the form of a motor 24 operatively connected to amixing blade 26 positioned within the interior region 30 of thecontainment vessel 16 and entirely beneath the surface of the water 14as shown). The stirring system 22 is used to agitate the supply of water14 and materials added thereto so that complete dissolution of thedelivered materials will occur in an efficient manner to produce maximumX-AOM yields.

After addition of the ADM 12 (e.g. the first reagent in this embodiment)to the supply of water 14 within the containment vessel 16, the ADM 12will rapidly dissolve (especially if agitated as noted above) to yieldan ADM-containing solution designated herein as an “aqueous isintermediate product” 32. At this point, further information is relevantregarding the amount of the ADM 12 to be employed in producing theaqueous intermediate product 32. While the claimed invention shall notbe restricted to any given amounts of added ADM 12 as the first reagentin this embodiment, optimum results will be achieved if about 275-290grams of ADM 12 are used per liter of water 14. This value may be variedas needed in accordance with preliminary pilot studies involvingnumerous factors including the desired operating scale of the system 10.

After formation of the intermediate product 32 (e.g. the supply of water14 having the ADM 12 dissolved therein), a supply of molybdenum trioxide34 (also known as “molybdic oxide” or “MoO₃”) is provided. In thepresent embodiment, the supply of molybdenum trioxide shall bedesignated herein and selected for use as the “second reagent”. Thematerial to be employed in connection with the second reagent may bedifferent in the other embodiments of the claimed process as discussedfurther below. The supply of molybdenum trioxide 34 can be obtained frommany different commercial sources including but not limited to theClimax Molybdenum Company of Ft. Madison, Iowa (U.S.A.). Likewise, allof the embodiments described herein shall not be limited to anyparticular types of molybdenum trioxide (or methods of production).However, best results are achieved if the molybdenum trioxide 34 is ofsufficiently high purity to contain not more than about 0.5% by weight(total) of non-molybdenum trioxide materials including iron (Fe),potassium (K), copper (Cu), lead (Pb), calcium (Ca), or other comparablematerials in both elemental and compound form. Likewise, in arepresentative embodiment, the molybdenum trioxide 34 employed at thisstage of the manufacturing process will have an exemplary particle sizeof about 10-400 microns although this value may be varied if needed anddesired. Representative production methods which can be employed inconnection with the supply of molybdenum trioxide 34 range from theroasting of molybdenum sulfide (“MoS₂”) to form molybdenum trioxide asdiscussed in U.S. Pat. No. 4,046,852 to the use of a multi-slurryoxidation process as indicated in co-owned U.S. Pat. No. 5,820,844, withboth of these documents being incorporated herein by reference.

It should also be noted that any terminology in the present descriptionwhich indicates that the ADM 12 or molybdenum trioxide 34 is “added”,“combined”, “provided”, or otherwise delivered into the system 10 shallinvolve the use of these compositions in a pre-manufactured form or thedelivery of “precursor” materials which, when added, react in situ toform the desired reagent(s).

While the precise reaction kinetics and molecular interactionsassociated with the formation of X-AOM over other AOM isomers withinsystem 10 are not entirely understood, is currently believed that themanner in which the molybdenum trioxide 34 (e.g. the second reagent) isdelivered into the system 10 in the current embodiment assists inpromoting the preferential formation of X-AOM in most cases. Themolybdenum trioxide 34 is preferably added to the aqueous intermediateproduct 32 in a gradual, non-instantaneous manner in accordance with thedefinition of this phrase provided above. This technique is againemployed in order to avoid delivering the supply of molybdenum trioxide34 to the intermediate product 32 in a single large quantity (e.g. allat once). To accomplish this goal, the molybdenum trioxide 34 may bedelivered in a continuous, progressive, and uniform manner over time orin discrete allotments added at periodic intervals. However, in apreferred and non-limiting embodiment, continuous, progressive, anduniform addition of the molybdenum trioxide 34 over a selected timeperiod is employed in order to ensure maximum yields of high-purityX-AOM.

The gradual, non-instantaneous addition of the molybdenum trioxide 34can be physically accomplished through the use of a standardcontrolled-delivery conveyor apparatus 36 which may involve aconventional screw-type transfer system or other functionally-equivalentmaterial handling device known in the art for continuous orinterval-based material transfer. It should also be noted that theapparatus 36 can be employed for delivering the ADM 12 into the supplyof water 14 (if gradual delivery is desired). Likewise, the apparatus 36may be used to deliver any other reagent into the system 10 in agradual, non-instantaneous manner when this type of delivery techniqueis needed and desired.

While the claimed method shall not be restricted to any particular rateat which gradual, non-instantaneous delivery of the molybdenum trioxide34 may be achieved, it is preferred that such delivery be undertaken atan overall rate of about 65-130 kilograms of molybdenum trioxide 34 perminute. In any given situation, the precise delivery rate associatedwith the molybdenum trioxide 34 (or any other materials to betransferred in a gradual, non-instantaneous manner as discussed herein)shall again be determined in accordance with routine pre-productiontesting taking into account the desired production-scale and otherrelated factors. The method described herein (including all embodiments)shall also not be limited to any particular numerical quantities inconnection with the supply of molybdenum trioxide 34 (and supply of ADM12). It is nonetheless preferred that such materials be employed in theapproximate stoichiometric proportions provided by the following basicchemical reaction:

2(NH₄)₂Mo₂O₇+4MoO₃→X−(NH₄)₄Mo₈O₂₆(or “X-AOM”)   (6)

However, to achieve optimum results, tests have demonstrated that theuse of molybdenum trioxide 34 in a slight excess of stoichiometricrequirements (e.g. about 1-5% by weight excess molybdenum trioxide 34)is preferred. Translated into numerical terms, optimum results areachieved if about 0.85-0.89 grams of molybdenum trioxide 34 are used pergram of ADM 12. Notwithstanding the information provided above, specificreagent quantities to be employed in a given situation are again bestdetermined through routine preliminary testing.

In accordance with the steps provided above in which the water 14, ADM12, and molybdenum trioxide 34 are all combined, a reaction product isgenerated which shall be designated herein as an “aqueous chemicalmixture” 50. Further treatment of this mixture 50 to obtain X-AOM andother important related information will be provided below.

As previously noted, the aqueous chemical mixture 50 in the presentembodiment is produced by (1) combining the supply of water 14 with theADM 12 which is used as the first reagent to yield the aqueousintermediate product 32; and (2) adding the molybdenum trioxide 34 (asthe second reagent) to the intermediate product 32 in a gradual,non-instantaneous manner (defined above) to yield the aqueous chemicalmixture 50. While this method is generally preferred and provides highlyeffective results with minimal labor, other comparable procedures can beemployed for producing the aqueous chemical mixture 50. Thesealternative methods each involve a different order in which the variousreagents (e.g. ADM 12 and molybdenum trioxide 34) are delivered into thesystem 10.

A second embodiment of the invention is shown within dashed box 52 inFIG. 1. As a preliminary note, all of the basic procedures, equipment,operational parameters, and other factors discussed above in connectionwith the first embodiment (including pre-heating of the water 14 to thepreviously-listed temperature, agitation of the liquid components in thesystem 10, and the like) are substantially identical to those used inthe second embodiment. The applicability of this information to thesecond embodiment is confirmed and represented by the use of commonreference numbers in both embodiments for the various components of thesystem 10 including the heating unit 20, the stirring system 22(consisting of the motor 24 and the mixing blade 26), and the like.Thus, all of the information, data, and techniques discussed above inconnection with the first embodiment are incorporated by referencerelative to the second embodiment unless otherwise indicated herein. Theonly substantial difference between both embodiments involves the orderin which the supplies of ADM 12 and molybdenum trioxide 34 are addedinto the system 10 which will now be discussed.

With continued reference to the dashed box 52 in FIG. 1, the supply ofmolybdenum trioxide 34 is initially combined with the supply of water14. In the previous embodiment, the ADM 12 was initially added to thewater 14, followed by the molybdenum trioxide 34. Thus, the order ofcomponent addition associated with the second embodiment is reversedcompared with the first embodiment. As a result, the supply ofmolybdenum trioxide 34 is selected for use as the “first reagent” inthis embodiment (since it is being added first), with the supply of ADM12 being designated for use as the “second reagent”. Addition of themolybdenum trioxide 34 to the water 14 may be accomplished eitherinstantaneously (e.g. all at once) or in a gradual, non-instantaneousmanner (defined above) at a representative rate of about 65-130kilograms of molybdenum trioxide 34 per minute. While the particularaddition technique used in connection with the supply of molybdenumtrioxide 34 as the first reagent shall not be considered critical,gradual, non-instantaneous addition of this material as defined above ispreferred in order to ensure rapid and complete dissolution of themolybdenum trioxide 34 within the supply of water 14. In this manner, anaqueous intermediate product 54 is generated (FIG. 1) which involves thesupply of water 14 having the molybdenum trioxide 34 dissolved therein.Regarding the amount of the molybdenum trioxide 34 which is used to formthe intermediate product 54, the present invention shall again not berestricted any particular quantity values which may be determined bypreliminary pilot testing. However, it is preferred that about 240-252grams of molybdenum trioxide 34 be used per liter of water 14 to achievemaximum X-AOM yields and purity values. Likewise, it should be notedthat the intermediate product 54 has been given a different referencenumber compared with intermediate product 32 in the first embodimentsince both products 32, 54 have a different chemical character.Specifically, intermediate product 32 in the first embodiment involves asolution containing dissolved ADM therein, while intermediate product 54consists of a solution made from dissolved molybdenum trioxide.Regardless of the chemical content of the intermediate products 32, 54,they will both effectively produce the aqueous chemical mixture 50(although the method of the first embodiment is again preferred fortechnical, ease-of-use, and solubility reasons).

After formation of the aqueous intermediate product 54 (which containsthe supply of water 14 and dissolved molybdenum trioxide 34 therein),the supply of ADM 12 is preferably added to the intermediate product 54in a gradual, non-instantaneous manner as defined above in order toavoid delivery of the entire supply of ADM 12 to the intermediateproduct 54 at the same time (e.g. in one large mass). To accomplish thisgoal, the ADM 12 may be delivered in a continuous, progressive, anduniform manner over time or in discrete allotments added at periodicintervals. In a preferred and non-limiting embodiment, continuous,progressive, and uniform addition of the ADM 12 over a selected timeperiod is employed in order to ensure maximum yields of high-purityX-AOM. The benefits provided by a gradual, non-instantaneous addition ofthis material are discussed above in connection with the firstembodiment and are equally applicable to the second embodiment.

The gradual, non-instantaneous addition of the ADM 12 can be achieved byusing controlled-delivery conveyor apparatus 36 discussed above whichmay again involve a conventional screw-type transfer system or otherfunctionally-equivalent material handling device known in the art forcontinuous or interval-based material transfer. It should also be notedthat the apparatus 36 can be employed for initially delivering themolybdenum trioxide 34 into the supply of water 14 in this embodiment(if gradual delivery is desired). Likewise, the apparatus 36 may be usedto deliver any other reagent into the system 10 in a gradual,non-instantaneous manner when this type of delivery technique is neededand desired as indicated above.

While this embodiment of the claimed process shall not be restricted toany particular rate at which gradual, non-instantaneous delivery of theADM 12 (e.g. the second reagent in the current embodiment) may beaccomplished, it is preferred that such delivery be undertaken at anoverall rate of about 75-150 kilograms of ADM 12 per minute. In anygiven situation, the precise delivery rate associated with the supply ofADM 12 (or any other materials to be transferred in a gradual,non-instantaneous manner) shall again be determined in accordance withroutine pre-production testing taking into account the desiredproduction-scale and other related factors. The method described herein(including all embodiments) shall also not be restricted to anyparticular numerical quantities in connection with the supply ofmolybdenum trioxide 34 (and supply of ADM 12). It is nonethelesspreferred that such materials again be employed in the approximatestoichiometric proportions provided by the following basic chemicalreaction which was discussed above in connection with the firstembodiment and is equally applicable to the second embodiment:

 2(NH₄)₂Mo₂O₇+4MoO₃→X−(NH₄)₄Mo₈O₂₆(or “X-AOM”)  (7)

However, to achieve optimum results, tests have demonstrated that theuse of molybdenum trioxide 34 in a slight excess of stoichiometricrequirements (e.g. about 1-5% by weight excess molybdenum trioxide 34)is preferred. Translated into numerical terms, optimum results areachieved if about 0.85-0.89 grams of the molybdenum trioxide 34 are usedper gram of ADM 12 in all of the embodiments described herein.

In accordance with the procedure discussed above and shown schematicallyin dashed box 52, the aqueous chemical mixture 50 is again generated.The chemical mixture 50 in both of the foregoing embodiments issubstantially the same in content, form, and other parameters. The onlysubstantial difference between both embodiments again involves the orderin which the supplies of ADM 12 and molybdenum trioxide 34 are added. Atthis stage in the claimed process, the aqueous chemical mixture 50produced in accordance with the second embodiment (if used) is furtherprocessed in a manner which is common to all of the embodiments providedherein (discussed in greater detail below).

In addition to the first and second embodiments listed above, a stillfurther embodiment (e.g. a third embodiment) may be employed to producethe aqueous chemical mixture 50. The third embodiment is illustratedschematically in dashed box 56 (FIG. 1). It should again be noted thatall of the basic procedures, equipment, operational parameters, andother factors discussed above in connection with the first embodiment(including pre-heating of the water 14 to the previously-listedtemperature, agitation of the liquid components in the system 10, andthe like) are substantially identical to those associated with the thirdembodiment unless otherwise indicated herein. The applicability of thisinformation to the third embodiment is confirmed and represented by theuse of common reference numbers in both embodiments for the variouscomponents of the system 10 including the heating unit 20, the stirringsystem 22 (consisting of the motor 24 and the mixing blade 26), and thelike. Thus, all of the information, data, and techniques discussed abovein connection with the first embodiment are incorporated by referencerelative to the third embodiment. The only difference of consequencebetween the first, second, and third embodiments again involves theorder in which the supplies of ADM 12 and molybdenum trioxide 34 areadded into the system 10 as will now be discussed.

The third embodiment shown in dashed box 56 specifically involves asituation in which the supplies of ADM 12 and molybdenum trioxide 34 areboth added to the water 14 at the same time, but in a gradual,non-instantaneous manner as defined above. Since the ADM 12 andmolybdenum trioxide 34 are both combined with the water 14 in asimultaneous fashion, there are no specific materials designated asfirst and second reagents in this embodiment. Likewise, no aqueousintermediate products are generated as discussed below. The gradual,non-instantaneous, and simultaneous delivery of ADM 12 and molybdenumtrioxide 34 shown in FIG. 1 (dashed box 56) is designed to avoiddelivery of the entire supplies of ADM 12 and molybdenum trioxide 34 tothe water 14 at the same time (e.g. in one large mass associated witheach composition). To accomplish this goal, the supplies of ADM 12 andmolybdenum trioxide 34 may be delivered in a continuous, progressive,and uniform manner over time or in discrete allotments added at periodicintervals. In a preferred and non-limiting embodiment, continuous,progressive, and uniform addition of the ADM 12 and molybdenum trioxide34 over a selected time period is employed to ensure maximum yields ofhigh-purity X-AOM. The benefits provided by the gradual,non-instantaneous addition of these materials are discussed above inconnection with the previous two embodiments and are equally applicableto the third embodiment. Likewise, in the third embodiment, the deliveryprocess associated with the supplies of ADM 12 and molybdenum trioxide34 will both ideally begin at substantially the same time. However, theterm “simultaneously” as used in this embodiment shall involve a processin which at least part of the above-listed materials (e.g. ADM 12 andmolybdenum trioxide 34) enter the water 14 at the same time, regardlessof whether the delivery of one material is started before the othermaterial.

The gradual, non-instantaneous addition of the ADM 12 and molybdenumtrioxide 34 in this embodiment can be achieved by using thecontrolled-delivery conveyor apparatus 36 discussed above which mayagain involve a conventional screw-type transfer system or otherfunctionally-equivalent material handling device known in the art forcontinuous or interval-based material transfer. A separate apparatus 36can be employed for the supply of ADM 12 and the supply of molybdenumtrioxide 34 as shown in dashed box 56 of FIG. 1. However, in thealternative, both of these ingredients (the ADM 12 and molybdenumtrioxide 34) can be delivered into the water 14 within the containmentvessel 16 using a single conveyor apparatus 36 in which such materialsare effectively “mixed” during delivery.

While this embodiment of the claimed process shall not be restricted toany particular rate at which gradual, non-instantaneous, andsimultaneous delivery of the ADM 12 and molybdenum trioxide 34 may beaccomplished, it is preferred that such delivery be undertaken at thefollowing rates: (1) the ADM 12=about 75-150 kilograms per minute; and(2) the molybdenum trioxide 34=about 65-130 kilograms per minute. If asingle conveyor apparatus 36 is used to simultaneously deliver both ofthe above materials, it is preferred that a single delivery rate whichfalls within both of the above-listed ranges be selected to deliver thecombined ADM 12 and molybdenum trioxide 34. However, the precisedelivery rate associated with the supplies of ADM 12, molybdenumtrioxide 34, or any other materials to be delivered in a gradual,non-instantaneous manner as discussed herein shall again be determinedin accordance with routine pre-production testing taking into accountthe desired production-scale and other related factors. The claimedmethod (including all embodiments) shall also not be restricted to anyparticular numerical quantities in connection with the supplies of ADM12 and molybdenum trioxide 34. It is nonetheless preferred that suchmaterials again be employed in the approximate stoichiometricproportions provided by the following basic chemical reaction which wasdiscussed above in connection with the previous two embodiments and isequally applicable to the third embodiment:

2 (NH₄)₂Mo₂O₇+4MoO₃→X−(NH₄)₄Mo₈O₂₆(or “X-AOM”)  (8)

However, to achieve optimum results, tests have demonstrated that theuse of molybdenum trioxide 34 in a slight excess of stoichiometricrequirements (e.g. about 1-5% by weight excess molybdenum trioxide 34)is preferred. Translated into numerical terms, optimum results areachieved if about 275-290 grams of ADM 12 are used per liter of water14, with about 0.85-0.89 grams of molybdenum trioxide 34 being used pergram of ADM 12.

In accordance with the procedure discussed above and shown schematicallyin dashed box 56, the aqueous chemical mixture 50 is again generated,with the subsequent treatment thereof being outlined further below.However, in this embodiment, the combined, simultaneous addition of thesupplies of ADM 12 and molybdenum trioxide 34 to the water 14 avoids thegeneration of any intermediate products and instead directly producesthe aqueous chemical mixture 50 as illustrated in FIG. 1. The aqueouschemical mixture 50 in all of the foregoing embodiments is substantiallythe same in content, form, and other parameters. The only difference ofconsequence between all of the embodiments again involves the order inwhich the supplies of ADM 12 and molybdenum trioxide 34 are added intothe system 10.

Regardless of which embodiment is employed to produce the aqueouschemical mixture 50, it is believed that the gradual delivery processdiscussed above contributes to the overall efficiency of the system 10in generating high yields of the X-AOM isomer in an effective manner.This gradual delivery procedure apparently results in a series ofcomplex kinetic interactions which are not yet entirely understood butenable the X-AOM isomer to be preferably generated (in most situations)over other AOM isomers (including α-AOM). As previously noted, theclaimed invention shall not be restricted to any given order in whichthe ADM 12 and molybdenum trioxide 34 are combined with the water 14,and which of these materials should be added in a gradual,non-instantaneous manner. However, in a process which does not involveadding the ADM 12 and molybdenum trioxide 34 simultaneously as definedabove, the composition that is added to the intermediate product 32 or54 (e.g. the “second reagent”) should optimally be delivered in agradual, non-instantaneous manner to achieve maximum, high-purity yieldsof X-AOM. Likewise, if the ADM 12 and molybdenum trioxide 34 aredelivered to the supply of water 14 simultaneously as discussed above,they should both be added in a gradual, non-instantaneous fashion toobtain best results. Again, it is currently believed that this processmaximizes the yield and purity levels of the resulting X-AOM product inmost cases.

With continued reference to FIG. 1, the aqueous chemical mixture 50(regardless of the manner in which it is generated) is thereafterprocessed to obtain a purified X-AOM product. To accomplish this goal,the aqueous chemical mixture 50 is heated within the containment vessel16 to further promote maximum X-AOM formation. This particular step cantake place within the containment vessel 16 as illustrated in FIG. 1 or,in the alternative, may be undertaken in a separate vessel (not shown)of the same type, size, and construction material as the vessel 16(depending on the desired scale of the system 10 and other relatedfactors).

The heating process associated with the aqueous chemical mixture 50 inthe containment vessel 16 preferably involves heating the mixture 50 toa temperature of about 85-90° C. which is maintained over a time periodthat preferably exceeds 3 hours (e.g. optimally about 3.5-5 hours).Heating is accomplished in the embodiment of FIG. 1 using the heatingunit 20 discussed above. Likewise, optimum results will be achieved ifthe chemical mixture 50 is constantly agitated (e.g. stirred) during theheating process to ensure maximum yields of X-AOM with high purityvalues. Agitation may be undertaken using the stirring system 22 whichagain includes a motor 24 operatively connected to a rotatable mixingblade 26 positioned within the interior region 30 of the vessel 16 (andentirely beneath the surface of the aqueous chemical mixture 50.)

It is also believed that, regardless of whether or not gradual,non-instantaneous delivery techniques are employed, heating inaccordance with the particular operational parameters recited herein(especially in excess of 3 hours) contributes to the preferentialgeneration of X-AOM while avoiding the production of other AOM isomersincluding α-AOM. Again, while the exact isomerization reactions whichpromote the formation of X-AOM over other AOM isomers are not entirelyunderstood, the specific heating process discussed above (and numericalparameters associated therewith including the heating time exceeding 3hours) apparently creates a unique chemical environment which promotesX-AOM formation. Optimum results will be achieved if the above-describedheating process is used in combination with gradual, non-instantaneousdelivery techniques as described herein.

As a result of the heating process, the aqueous chemical mixture 50 isbasically converted into a thickened slurry-type composition havingsolid X-AOM suspended therein which shall be characterized as a“reaction product” 60 schematically illustrated in FIG. 1. The reactionproduct 60 basically includes (1) a liquid fraction 62 consistingprimarily of water derived from the original supply of water 14 alongwith very small amounts of residual dissolved ADM and/or molybdenumtrioxide; and (2) a suspended solid fraction 64 that consistsessentially of the desired X-AOM product, the unique characteristics ofwhich will be summarized below. After the heating process is completed,the reaction product 60 is preferably cooled in an optional coolingstage. Cooling in the embodiment of FIG. 1 again optimally occurs withinthe containment vessel 16 although a separate vessel (not shown) of thesame type, size, and construction material as the vessel 16 can beemployed for this purpose, depending on the desired scale of the system10 and other related factors.

Cooling of the reaction product 60 at this stage provides a number ofadvantages including the promotion of X-AOM crystal formation and growth(which leads to improved handleability characteristics). Cooling of thereaction product 60 inside the containment vessel 16 may occur via thedeactivation of heating unit 20 and the natural dissipation of heat overtime without the use of external cooling aids or systems. While theclaimed invention shall again not be specifically limited to anyparticular cooling temperatures, optimum results are achieved if thereaction product is cooled to about 60-70° C. which is designed toprovide additional ease of handling, further X-AOM crystal growth, andthe like. Alternatively (and in a preferred embodiment), the coolingprocess may be accelerated through the use of an optional cooling unit(not shown) of conventional design associated with the containmentvessel 16 and positioned on the inside or outside thereof.Representative systems suitable for use as the cooling unit may includebut are not limited to standard chiller coil/refrigeration systems orwater cooling devices that are known in the art for the large-scalecooling of industrial fluids. Likewise, if the heating unit 20 is of atype which employs circulating hot water or steam therein to increasethe temperature of the containment vessel 16 and its contents, coldwater may likewise be routed through the unit 20 for cooling purposes ifdesired.

After cooling of the reaction product 60 (if desired), the product 60 isoptionally transferred out of the containment vessel 16 in theembodiment of FIG. 1 and routed into a temporary storage vessel 70. In apreferred embodiment, the storage vessel 70 is of the same type, size,and construction material as the vessel 16 or otherwise configured asneeded. The next step (which is also optional but beneficial incharacter) involves a procedure in which a portion 72 of the reactionproduct 60 is routed (e.g. recycled) from the storage vessel 70 backinto the initial containment vessel 16 at the beginning of the system 10as illustrated in FIG. 1. This portion 72 of the reaction product 60will again include a supply of X-AOM therein from the previous (e.g.prior) processing sequence discussed above. The portion 72 of thereaction product 60 that is transferred back to the vessel 16 functionsas a “seed” composition that promotes favorable reaction kinetics withinthe vessel 16 which lead to improved X-AOM yield characteristics and amore easily handled product with beneficial physical characteristics(e.g. a greater overall density). While the claimed process shall not berestricted to any particular quantity in connection with the recycledportion 72, it is preferred that about 5-15% by weight of the reactionproduct 60 be used as the portion 72. In systems which do not employ aseparate storage vessel 70 as shown in FIG. 1, the “seeding” processoutlined above may be accomplished by simply leaving about 5-15% byweight (or other selected amount as needed and desired) of the reactionproduct 60 within the containment vessel 16 after the majority of theproduct 60 is removed for subsequent treatment (e.g. by filtration andthe like as indicated below). Thus, this aspect of the present inventionin its broadest sense involves combining a supply of previously-producedX-AOM (derived from the portion 72) with the ADM 12, water 14, andmolybdenum trioxide 34 (regardless of the order and manner of addition[e.g. gradual or non-gradual]) to yield additional supplies of X-AOMhaving the beneficial physical characteristics listed above. It shouldnonetheless be emphasized that this “seeding”/recycling stage isoptional, with the use thereof being employed in accordance withpreliminary routine testing, taking into consideration the particularreaction conditions and production-scale of interest.

Next, the reaction product 60 within the storage vessel 70 is treated toremove/recover the X-AOM-containing solid fraction 64 from the liquidfraction 62. This may be achieved in many different ways, with thepresent invention not being limited to any particular isolation methods.For example, in a preferred and non-limiting embodiment illustratedschematically in FIG. 1, the slurry-type reaction product 60 containingthe liquid and solid fractions 62, 64 is passed through a selectedfiltration system 74. Many different components and materials can beemployed in connection with the filtration system 74. However,representative and non-limiting examples of filtration devices which canbe used in connection with the filtration system 74 include but are notlimited to vacuum and/or pressure-type filters as discussed furtherbelow in the Example section. Other removal devices may also be employedfor separating the X-AOM-containing solid fraction 64 from the liquidfraction 62 in the reaction product 60 include conventional centrifugesystems, settling units, cyclones, and the like.

In accordance with the recovery/filtration process shown in FIG. 1 anddiscussed above, a retentate 76 and a permeate 80 are generated. Theretentate 76 involves the isolated solid fraction 64, namely, an X-AOMcrystalline product having a representative purity level of about +95%by weight X-AOM. The retentate 76 may optionally be washed one or moretimes with water if needed and desired. The permeate 80 consists of theliquid fraction 62 which again comprises mostly water and residualdissolved quantities of the various molybdenum-based chemical speciesused in the system 10. These species include relatively insignificantamounts of dissolved ADM and dissolved molybdenum trioxide. The permeate80 can either be discarded or further treated to recover molybdenumtherefrom. While the recovery/filtration step discussed above is shownonly once in FIG. 1, multiple, successive recovery stages can be used ifnecessary.

The retentate 76 consisting primarily of crystalline X-AOM can then beair dried or preferably dried one or more times (e.g. in single ormultiple drying stages) using a conventional oven apparatus 82illustrated schematically in FIG. 1. While the claimed method shall notbe restricted to any given heating systems in connection with the ovenapparatus 82, exemplary devices which may be used in connection with theoven apparatus 82 include but are not limited to steam or gas-heatedrotary dryer units, spray dryer systems, and combinations thereof.Likewise, the present invention shall not be limited to any specificparameters in connection with the drying process discussed above.However, in an exemplary embodiment, drying of the X-AOM-containingretentate 76 will typically occur at a temperature of about 145-150° C.for a time period of about 60-90 minutes (in a single drying stage). Anexample of a multiple drying process which may be employed in order toachieve more gradual and controlled drying will be discussed below inthe Example section.

The resulting dried composition obtained from the oven apparatus 82 willconsist of the final X-AOM product 84 shown in FIG. 1. If needed forparticular applications, the X-AOM product 84 may be ground or otherwisesize-reduced using conventional grinding systems (not shown). It isdesired in most cases for the final X-AOM product 84 to have an averageparticle size of about 16 microns or less. The X-AOM product 84 (which,again, is typically about +95% by weight X-AOM) may thereafter be storedfor future use or otherwise immediately utilized in a variety ofimportant applications including incorporation within various polymericplastic materials (e.g. electrical or fiber-optic cable coverings madeof rigid PVC) as a highly effective smoke suppressant with increasedthermal stability. As previously noted, the X-AOM product 84 is able toprovide superior smoke suppressant (and flame retardant) characteristicscompared with other AOM isomers (including α-AOM). For example, testshave shown that X-AOM can offer a greater degree of smoke-suppressionper unit volume compared with other AOM isomers such as α-AOM. Theprocess discussed above and the resulting X-AOM product 84 thereforerepresent a considerable advance in the art of molybdenum technology.

In order to provide further information regarding a preferred andenabling process which may be used to yield substantial amounts of X-AOMat high purity levels (e.g. +95% by weight X-AOM), the following Exampleis provided. It shall be understood that the Example presented below isrepresentative only and is not intended to limit the invention in anyrespect.

EXAMPLE

In this Example, about 8025 liters of deionized water were initiallyprovided and placed in a containment vessel of the type discussed abovehaving a capacity of about 22,700 liters. Also combined with the waterwas about 2270 liters of the X-AOM-containing aqueous chemical mixture(defined above) obtained from the previous production run. This materialagain functions as a “seed” composition as previously noted. A supply ofADM having a particle size of about 22-26 microns was added to the water(and “seed” material) to produce an aqueous intermediate product.Addition of the ADM to the water was undertaken in a gradual,non-instantaneous manner as defined above. Addition of the ADM wasaccomplished using a screw conveyor apparatus of conventional design. Inthis Example, about 283 grams of ADM were used per liter of water. Thisresulted in the use of a grand total of about 2268 kilograms of ADMwhich were delivered into the water at a rate of about 110 kilograms ofADM per minute.

Thereafter, a supply of molybdenum trioxide having a particle size ofabout 380 microns was added to the aqueous intermediate product in agradual, non-instantaneous manner (discussed above) at a rate of about95 kilograms of molybdenum trioxide per minute. The total amount ofmolybdenum trioxide used in this Example was about 1973 kilograms (e.g.about 0.87 grams of molybdenum trioxide per gram of ADM). Addition ofthe molybdenum trioxide was also achieved using a conventional screwconveyor apparatus. As a result of these steps, an aqueous chemicalmixture was produced from the water, ADM, and molybdenum trioxide.

Next, while maintaining the aqueous chemical mixture within thecontainment vessel, it was heated for about 4.5 hours at a temperatureof about 88° C. (with agitation as discussed above) to produce aslurry-type reaction product. Thereafter, the reaction product wascooled to about 66° C. within the containment vessel. Cooling wasaccomplished through the use of a conventional water-based cooling coilsystem associated with the containment vessel and in physical contacttherewith in which cooling water (at a temperature of about 23° C. ) wastransferred therethrough. Cooling occurred over a time period of about60 minutes. The cooled reaction product which contained the solid X-AOMcomposition of interest therein was then routed into a separatepre-filtration storage vessel.

After transfer of the cooled reaction product to the storage vessel,about 10% by weight of the cooled reaction product was sent back intothe initial containment vessel to act as a “seed” formulation for theenhanced production, generation, and growth of X-AOM crystals insubsequent production runs which will again improve the handleability ofthe X-AOM product by increasing its overall density. Next, the cooledproduct was routed into a filtration system which, in this Example,involved a pressure-based filter unit of a type obtainable from numeroussuppliers including the Larox Corporation of Patuxent Woods Drive,Columbia Md. (U.S.A.). Filtration occurred over a time period of about24 hours (to process the complete amount of material which wasrecovered/filtered in individual batches).

The resulting filtered product (consisting of X-AOM) was then directedinto a conventional continuously-operating rotary primary dryingapparatus heated by natural gas (or steam) to a temperature of about140° C. over a time period of about 1 hour (making certain that thetemperature did not exceed about 230-250° C. which can result in thermaldecomposition of the desired materials.) Thereafter, the dried X-AOM wasreduced to a particle size of about 150 microns or less using a materialhandling apparatus suitable for this purpose (e.g. a hammermill),followed by transfer of the size-reduced X-AOM into a secondary dryingapparatus (e.g. of a conventional vertical type which is obtainable frommany different sources including the Wyssmont Co., Inc. of Fort Lee,N.J. (U.S.A.) under the trademark “TURBO-DRYER”.) Within the secondarydrying apparatus, the X-AOM was heated to a temperature of about 110° C.over a time period of about 1 hour. The dried X-AOM was then subjectedto additional grinding/size reduction in a primary grinding unit (e.g. amill/grinding system of a type obtainable from many sources includingHosokawa Micron Powder Systems of Summit, N.J. [U.S.A.] under thetrademark “Mikro-ACM”) so that the X-AOM product was furthersize-reduced to a particle size not exceeding about 30 microns.

Finally, after treatment in the primary grinding unit, the particulateX-AOM was further dried in a tertiary drying apparatus (e.g. of the sametype as employed in connection with the secondary drying apparatuslisted above) at about 110° C. for a time period of about 3 hours toyield the final X-AOM product. This product was further size-reduced ina secondary grinding unit of the same type as the primary grinding unitlisted above to a particle size of about 16 microns or less.

Again, the claimed method shall not be restricted to the parameters,equipment, processing sequences, and other information set forth in thisExample which are provided for informational purposes.

B. Characteristics of the Completed X-AOM Product

As previously noted, the X-AOM composition of the present invention hasa unique isomeric configuration which differs substantially from that ofother AOM isomers including α-AOM and β-AOM (well as the γ and δ formsof AOM). The X-AOM product is readily characterized (and clearlydistinguished from other forms of AOM) using its unique Raman spectralprofile. Raman spectroscopy basically involves the collection ofspectral intensity values which result when light obtained from ahigh-energy source (e.g. a quartz-mercury lamp or argon-ion laser unit)is passed through a substance. Raman spectroscopy is an establishedanalytical technique that provides highly accurate and definitiveresults. In accordance with the present invention, Raman spectralanalysis of the novel X-AOM product results in a distinctive spectralprofile which is entirely different from the spectral profiles of otherAOM isomers. Raman spectroscopy specifically provides detailed covalentchemical bonding information, and likewise graphically illustratesmedium and long range order modes in connection with the compounds beinganalyzed. Further general information concerning Raman spectroscopy isprovided in U.S. Pat. No. 5,534,997 which is incorporated herein byreference. The use of Raman spectral analysis represents the mostfeasible and practical way that is currently known for theidentification of X-AOM, with this method being accurate, repeatable,and subject to minimal error. It is therefore entirely sufficient,enabling, and definitive for the novel X-AOM isomer to be claimed andcharacterized (e.g. identified) spectrally, particularly using Ramanspectral analysis. Basically, the presence of intensity peaks in onespectral profile which do not appear in other spectral profiles supportsthe existence of a different and distinctive compound (X-AOM in thiscase).

To confirm the distinctive character of X-AOM, its Raman spectralprofile was compared with the Raman spectral profiles obtained fromα-AOM and β-AOM. Many different Raman spectral analyzers may be usedwith consistent results. Accordingly, analysis of the X-AOM productusing Raman spectroscopy shall not be restricted to any particularanalyzing equipment. For example, Raman spectral analysis servicessuitable for use in identifying X-AOM are available from many commercialenterprises including Namar Scientific, Inc. of McKeesport, Pa. (U.S.A.)which employs a Model 1000 Raman Spectrometer produced by the RenishawCompany of Schaumburg, Ill. (U.S.A.). This particular system uses a514.5 nm (2 mW) argon-ion laser excitation source, with a 1800 groove/mmgrating that allows a 1.5 cm⁻¹ spectral resolution. A spectral region of100-4000 cm⁻¹is utilized, with detection/analysis being accomplishedusing a −70° C. Peltier-cooled CCD detector. A microscope having 10x,20x, and 50x objectives is ultimately employed to collect scatteredradiation obtained from the laser-illuminated samples, with thescattered radiation thereafter being directed into the Ramanspectrometer described above. Notwithstanding the availability of thisparticular system for testing purposes involving X-AOM, the claimedinvention shall not be restricted to any particular Raman-typeanalytical equipment, with many different systems and configurationsproviding equivalent results.

With reference to FIG. 2, a Raman spectral profile 100 of the X-AOMproduct is provided. At the outset, it is important to note that thevarious peaks which are not identified or otherwise discussed inconnection with the profiles of FIGS. 2-4 involve other species, phases,and/or by-product molybdates (e.g. trace impurities) which constitutenon-AOM contaminates. The peaks to be discussed below involve thosewhich are unique to the products being analyzed and can be used todistinguish one product from another. The profile 100 of X-AOM wasgenerated at Iowa State University in Ames, Iowa (U.S.A.) using thefollowing type of Raman spectral analyzer: Spex Triplemate Model 1877produced by Instruments, SA of Edison, N.J. (U.S.A.). As illustrated inFIG. 2, the spectral profile of X-AOM includes three main peaks asfollows (with the term “main peaks” denoting peaks for a given AOMisomer which are not present in the Raman spectral profiles of other AOMisomers): (1) Peak #1 shown at reference number 102=953-955 cm⁻¹; (2)Peak #2 shown at reference number 104=946-948 cm⁻¹; and (3) Peak #3shown at reference number 106=796-798 cm⁻¹. These values are expressedin ranges to account for a minor degree of experimental variation whichexists between individual Raman spectral analyzers (e.g. from one typeor brand to another). The Raman spectral profile 100 of FIG. 2 isentirely distinctive compared with the Raman data obtained from theα-AOM and β-AOM isomers (discussed below), with peaks 102, 104, and 106being absent from the profiles described below. Thus, X-AOM represents anew and distinctive compound which is structurally different from otherAOM isomers.

FIG. 3 involves a Raman spectral profile 200 of α-AOM. The spectralprofile 200 was generated using the same equipment and parameters thatwere employed in producing the spectral profile 100 of FIG. 2. Asillustrated in FIG. 3, the spectral profile 200 of α-AOM includes onlytwo main peaks as follows: (1) Peak #1 shown at reference number202=964-965 cm⁻¹; and (2) Peak #2 shown at reference number 204=910-911cm⁻¹. Comparing FIGS. 2 and 3, the number of peaks and themagnitudes/locations of the peaks are significantly different. Also,peaks 202, 204 are not present in FIG. 2. In accordance with thesensitive and accurate nature of Raman spectroscopy, the significantdifferences between X-AOM and α-AOM are clearly demonstrated using theinformation presented above which supports the novelty of X-AOM.

Finally, in FIG. 4, a Raman spectral profile 300 of β-AOM is provided.The spectral profile 300 was generated using the same equipment andparameters that were employed in producing the spectral profile 100 ofFIG. 2. As illustrated in FIG. 4, the spectral profile 300 of β-AOMincludes only two main peaks as follows: (1) Peak #1 shown at referencenumber 302=977-978 cm⁻¹; and (2) Peak #2 shown at reference number304=900-901 cm⁻¹. Comparing FIGS. 2 and 4, the number of peaks and themagnitudes/locations of the peaks are significantly different. Also,peaks 302, 304 are not present in FIG. 2. In accordance with thesensitive and accurate nature of Raman spectroscopy, the significantdifferences between X-AOM and β-AOM are likewise demonstrated using theinformation presented above which again supports the novelty of X-AOM.

It is readily apparent that the process discussed herein creates a new,unique, and distinctive form of ammonium octamolybdate which likewisehas improved functional capabilities. This is especially true inconnection with the superior smoke suppressant capacity of X-AOMcompared with other AOM isomers including α-AOM. It has again beendetermined in various applications that effective smoke suppression willoccur using reduced amounts of X-AOM as an additive to, for example,polymer plastics, compared with conventional α-AOM and β-AOM. The X-AOMproduct is also characterized by high levels of uniformity and purity.Thus, X-AOM has a greater degree of functional efficiency in accordancewith the different structural characteristics of this material relativeto other AOM isomers.

In conclusion, the claimed product and process collectively represent animportant development in molybdenum technology. The X-AOM compositiondescribed above not only includes a unique isomeric structure (which isdifferent from all other AOM isomers), but likewise has improved smokesuppression qualities. The product and process discussed above arenovel, distinctive, and highly beneficial from a technical andutilitarian standpoint. Having herein set forth preferred embodiments ofthe present invention, it is anticipated that suitable modifications canbe made thereto which will nonetheless remain within the scope of theinvention. For example, the claimed process shall not be restricted toany particular operational parameters, processing equipment, and thelike unless otherwise noted herein. The invention shall therefore onlybe construed in accordance with the following claims:

The invention that is claimed is:
 1. A method for producing an ammoniumoctamolybdate isomer comprising: providing a supply of ammoniumdimolybdate, a supply of molybdenum trioxide, and a supply of water;selecting one of said supply of ammonium dimolybdate and said supply ofmolybdenum trioxide for use as a first reagent and another of saidsupply of ammonium dimolybdate and said supply of molybdenum trioxidefor use as a second reagent; combining said first reagent with saidwater to produce an intermediate product; adding said second reagent tosaid intermediate product in order to generate an aqueous chemicalmixture, said adding of said second reagent to said intermediate productcomprising delivering said second reagent to said intermediate productin a gradual, non-instantaneous manner in order to avoid delivery ofsaid second reagent to said intermediate product all at once; andheating said aqueous chemical mixture to produce a reaction productcomprising said ammonium octamolybdate isomer therein, said ammoniumoctamolybdate isomer having Raman spectra peaks at wavelength values ofabout 953-955 cm⁻¹, about 946-948 cm⁻¹, and about 796-798 cm⁻¹.
 2. Themethod of claim 1 further comprising removing said ammoniumoctamolybdate isomer from said reaction product.
 3. The method of claim1 wherein said heating of said aqueous chemical mixture occurs at atemperature of about 85-90° C. over a time period of about 3.5-5 hours.4. The method of claim 1 further comprising cooling said aqueouschemical mixture to a temperature of about 60-70° C. after said heatingthereof.
 5. A method for producing an ammonium octamolybdate isomercomprising: providing a supply of ammonium dimolybdate, a supply ofmolybdenum trioxide, and a supply of water; combining said supply ofammonium dimolybdate with said water to produce an intermediate product;combining said molybdenum trioxide with said intermediate product toproduce an aqueous chemical mixture, said combining of said molybdenumtrioxide with said intermediate product comprising adding saidmolybdenum trioxide to said intermediate product in a gradual,non-instantaneous manner at a rate of about 65-130 kilograms of saidmolybdenum trioxide per minute in order to avoid delivery of saidmolybdenum trioxide to said intermediate product all at once; andheating said aqueous chemical mixture to produce a reaction productcomprising said ammonium octamolybdate isomer therein, said ammoniumoctamolybdate isomer having Raman spectra peaks at wavelength values ofabout 953-955 cm⁻¹, about 946-948 cm⁻¹, and about 796-798 cm⁻¹.
 6. Themethod of claim 5 wherein said heating of said aqueous chemical mixtureoccurs at a temperature of about 85-90° C. over a time period of about3.5-5 hours.
 7. The method of claim 5 further comprising cooling saidaqueous chemical mixture to a temperature of about 60-70° C. after saidheating thereof.
 8. A method for producing an ammonium octamolybdateisomer comprising: providing a supply of ammonium dimolybdate, a supplyof molybdenum trioxide, and a supply of water; combining said molybdenumtrioxide with said water to produce an intermediate product; combiningsaid ammonium dimolybdate with said intermediate product to produce anaqueous chemical mixture, said combining of said ammonium dimolybdatewith said intermediate product comprising adding said ammoniumdimolybdate to said intermediate product in a gradual, non-instantaneousmanner at a rate of about 75-150 kilograms of said ammonium dimolybdateper minute in order to avoid delivery of said ammonium dimolybdate tosaid intermediate product all at once; and heating said aqueous chemicalmixture to produce a reaction product comprising said ammoniumoctamolybdate isomer therein, said ammonium octamolybdate isomer havingRaman spectra peaks at wavelength values of about 953-955 cm⁻¹, about946-948 cm⁻¹, and about 796-798 cm⁻¹.
 9. The method of claim 8 whereinsaid heating of said aqueous chemical mixture occurs at a temperature ofabout 85-90° C. over a time period of about 3.5-5 hours.
 10. The methodof claim 8 further comprising cooling said aqueous chemical mixture to atemperature of about 60-70° C. after said heating thereof.
 11. A methodfor producing an ammonium octamolybdate isomer comprising: providing asupply of ammonium dimolybdate, a supply of molybdenum trioxide, and asupply of water; combining said ammonium dimolybdate and said molybdenumtrioxide with said water to produce an aqueous chemical mixture, saidcombining of said ammonium dimolybdate and said molybdenum trioxide withsaid water comprising delivering both of said ammonium dimolybdate andsaid molybdenum trioxide to said water simultaneously, said ammoniumdimolybdate being delivered to said water in a gradual,non-instantaneous manner in order to avoid delivery of said ammoniumdimolybdate to said water all at once, said molybdenum trioxide beingdelivered to said water in a gradual, non-instantaneous manner in orderto avoid delivery of said molybdenum trioxide to said water all at once;and heating said aqueous chemical mixture to produce a reaction productcomprising said ammonium octamolybdate isomer therein, said ammoniumoctamolybdate isomer having Raman spectra peaks at wavelength values ofabout 953-955 cm⁻¹, about 946-948 cm⁻¹, and about 796-798 cm⁻¹.
 12. Themethod of claim 11 wherein said heating of said aqueous chemical mixtureoccurs at a temperature of about 85-90° C. over a time period of about3.5-5 hours.
 13. The method of claim 11 further comprising cooling saidaqueous chemical mixture to a temperature of about 60-70° C. after saidheating thereof.
 14. The method of claim 11 wherein said ammoniumdimolybdate is delivered to said water in said gradual,non-instantaneous manner at a rate of about 75-150 kilograms of saidammonium dimolybdate per minute.
 15. The method of claim 11 wherein saidmolybdenum trioxide is delivered to said water in said gradual,non-instantaneous manner at a rate of about 65-130 kilograms of saidmolybdenum trioxide per minute.
 16. A method for producing an ammoniumoctamolybdate isomer comprising: providing a supply of ammoniumdimolybdate, a supply of molybdenum trioxide, a supply of water, and apreviously manufactured supply of said ammonium octamolybdate isomer,said ammonium octamolybdate isomer having Raman spectra peaks atwavelength values of about 953-955 cm⁻¹, about 946-948 cm⁻¹, and about796-798 cm⁻¹, combining said ammonium dimolybdate, said molybdenumtrioxide, said supply of water, and said previously manufactured supplyof said ammonium octamolybdate isomer to produce an aqueous chemicalmixture; and heating said aqueous chemical mixture to yield a reactionproduct comprising additional amounts of said ammonium octamolybdateisomer therein, said additional amounts of ammonium octamolybdate isomerhaving Raman spectra peaks at wavelength values of about 953-955 cm⁻¹,about 946-948 cm⁻¹, and about 796-798 cm⁻¹.
 17. A method for producingan ammonium octamolybdate isomer comprising: providing a supply ofammonium dimolybdate, a supply of molybdenum trioxide, and a supply ofwater; combining said ammonium dimolybdate, said molybdenum trioxide,and said water to produce an aqueous chemical mixture; and heating saidaqueous chemical mixture at a temperature of about 85-90° C. for a timeperiod exceeding 3 hours to produce a completed reaction productcomprising said ammonium octamolybdate isomer therein, said ammoniumoctamolybdate isomer having Raman spectra peaks at wavelength values ofabout 953-955 cm⁻¹, about 946-948 cm⁻¹, and about 796-798 cm⁻¹.
 18. Amethod for producing an ammonium octamolybdate isomer comprising:providing a supply of ammonium dimolybdate, a supply of molybdenumtrioxide, and a supply of water; combining said ammonium dimolybdatewith said water to produce an intermediate product, with about 283 gramsof said ammonium dimolybdate being used per liter of said water;combining said molybdenum trioxide with said intermediate product toproduce an aqueous chemical mixture, with about 0.87 grams of saidmolybdenum trioxide being used per gram of said ammonium dimolybdate,said combining of said molybdenum trioxide with said intermediateproduct comprising adding said molybdenum trioxide to said intermediateproduct in a gradual, non-instantaneous manner at a rate of about 95kilograms of said molybdenum trioxide per minute in order to avoiddelivery of said molybdenum trioxide to said intermediate product all atonce; heating said aqueous chemical mixture at a temperature of about88° C. for a time period of about 4.5 hours to produce a reactionproduct comprising said ammonium octamolybdate isomer therein, saidammonium octamolybdate isomer having Raman spectra peaks at wavelengthvalues of about 953-955 cm⁻¹, about 946-948 cm⁻¹, and about 796-798cm⁻¹; cooling said reaction product to a temperature of about 66° C.after said heating thereof; and removing said ammonium octamolybdateisomer from said reaction product after said cooling thereof.